RE: Should I freak out!!??
Ok this is what I come up with using ontarget and adjusting it to your specs (300 grn arrow at 309 fps)
I used a 25 inch arrow with 90 grn broad head and 2 inch blazer vanes.
Your correct arrow length for a 26 inch draw length should be around 25.25 inches from nock groove to the end of the insert. I went with a 25 inch shaft length for my calculations. You must be shooting a shorter arrow though because I come up with a heavier arrow, unless the arrow you are shooting is not in my database. I have Radial X Stealth Hunters and Radial X Pro's. Both weigh the same and come up to about 310 grains for a finished arrow weight according to Ontarget. It isn't always dead on though.
I show the 200 being a near perfect spine match at 25 inches with your set up. The 300 shows up on the stiff side. And if you are shooting shorter arrows than 25 inches they are way stiff. If you are shooting 24 inch arrows they show up off the charts stiff. However the weight doesn't come out right, so I question the actual length.
If you can measure your arrows for shaft length for me and let me know what they are. Don't include the nock or insert, just the shaft. And then verify that they weigh what what you posted (344 grns finished arrow weight)
If your arrows vary from what I used let me know (2 inch blazer vanes and 90 grn tip weight).
For the 300's with your draw weight and draw length I show you needing almost a 29 inch arrow with a 90 grn tip in order to spine correctly. The only problem is you would have really low FOC, like 7 percent and an arrow weight of around 370 grns . Or you could go with the 300's using a 125 grn broad head and a 27 inch shaft length. I show this being the correct spine and it would give you an 11% or so FOC but it would put you at near 390 grns. ( I sort of like that one)
If your arrows are indeed 24 inch radial X 300's at 24 inches I show you needing close to a 250 grn tip weight in order to break down the spine correctly. Putting you at near 500 grn arrows! Which isn't really what you are looking for.
The 200's at 25 inches with a 90 grn tip spine almost perfect and give you a 9% FOC. This is what I would suggest with a 90 or 100 grn tip if you wanted the speed.
According to ontarget all of the above arrow combinations would still keep you above 250 fps.
Again I ask what was your reasoning in switching arrows in the first place? Where you looking for a heavier arrow? That is the only reason I see going to a heavier spine arrow. Choosing more spine lets you either go with a longer arrow or more tip weight in order to increase overall arrow weight. Or turn up your draw weight, but you are already maxed out from the looks of it.
This is why overdraws were so popular with aluminum arrows. It would let you shoot a shorter arrow and that meant you could drop to a weaker spine, the two combined meant you could shoot a much lighter arrow to increase speed.
I personally like a heavier arrow. I have a 26 inch draw length and draw around 60 lbs. I shoot a 27 inch aluminum arrow that weighs above 400 grns. I don't get much speed out of it though.
I just did some playing and another option for you would be to go with 100's at 24 inches long and use a 75 grn tip, then turn your poundage down to 63-65 lbs. It would still put you around 300 fps and it would be easier to draw. I honestly wouldn't suggest going that light on arrows though. Maybe for 3-d, but not for hunting.
I hope that helps you some. And remember these are not dead on accurate figures, sometimes you still need to play a little. However they are MUCH more accurate than the arrow charts, those things are pretty much useless sometimes.
On the upside your arrows are stiff, not weak. They may work ok for you, it would be worth trying first. However if you have trouble tuning them you will know why.
Paul